Rivers nourish the land, maintain ecological balance, and promote agricultural development, but if changes in the flow of major rivers are not known, floods or droughts may occur. From large rivers to small streams, velocity and flow monitoring has always been a concern for hydrographic measurements.

Legacy measurement equipment such as mechanical current meters, printed current meters, electromagnetic current meters, etc., can only measure single-point flow velocity and cannot accurately measure the cross-section flow.

The ADCP (Acoustic Doppler Velocity Profiler), which can measure the velocity of each layer of the entire section, providing a more intuitive and accurate visualization of streamflow, is now favored by most hydrographers.

The APACHE 4, an autonomous hydrographic survey USV, avoids the high maintenance cost of cableway towing. It is compact, easy to launch, and handle at the mission site. Moreover, it can be conveniently transported by car.

The APACHE 4 integrates a single beam echo sounder and ADCP to make up for the loss of ADCP’s bottom and compass tracking data, vulnerable to environmental conditions. This USV supports a wide variety of ADCP systems available on the market; it offers an unmanned operation solution with a shallow draft, high navigational accuracy, and stable hovering for hydrologists when measuring the current section’s water flow velocity and discharge.

The APACHE 4 USV brings together the best of high-accuracy positioning and automated navigation control technology, built around the operator’s habits when conducting ADCP hydrographic cross-section flow measurements. Even when obstructed environments might degrade GNSS positioning, the internal GNSS+IMU module provides a reliable position and heading for the ADCP and autopilot controller. As a result, the APACHE 4 is a perfect solution for obtaining high-quality flow and velocity measurements in water where manned boat access is impractical.

Water operations are one of the most dangerous industries today, where human factors cause approximately 70% of accidents. The integrated applications of USV have started to modify the working status of the relevant staff and ships. The staff is already partially transferred from the boats to the land when boats are equipped with smart sensors to navigate autonomously. As a result, the operating costs are reduced, and the efficiency and measurement accuracy are greatly improved.

The APACHE 4, Autonomous Flow Measurement USV, solves the problems related to the low navigation and measurement accuracy, short data transmission distance, low work efficiency, shore flow distance estimation that are so common in hydrological surveys. It meets the measurement specification requirements and innovates the way we do the hydrological survey.

Read more to learn about the key features of Apache 4 and see detailed project implementation here.